Sensitivity of South America Climate to Positive Extremes of Antarctic Sea Ice.

Global climate change is expected to increasingly affect climate-sensitive sectors of society, such as the economy and environment, with significant impacts on water, energy, agriculture and fisheries. This is the case in South America, whose economy is highly dependent on the agricultural sector. Here, we analyzed the sensitivity of South American climate to positive extremes of Antarctic sea ice (ASI) extent and volume at continental and regional scales.

Combined performance of September's Weddell sea ice extent, Southern Annular Mode, and Atlantic SST anomalies over the South American temperature and precipitation.

This paper aims to analyze the relationships among tropical (Atlantic Meridional Mode - AMM), subtropical (South Atlantic Subtropical Gradient - SASG), and extratropical (Southern Annular Mode - SAM) teleconnection patterns, the Weddell Sea (WS) sea ice extents, and the climate in South America. Warm anomalies are observed in most of South America for maximum WS ice extent combinations (negative SAM/positive AMM and negative SAM/positive SASG composites), with an opposite signal at tropical South America for minimum WS ice extent combinations (positive SAM/negative AMM and positive SAM/negative SASG). Over Southern Argentina, colder (warmer) temperatures are seen at the negative SAM/positive SASG (positive SAM/negative SASG).

Response of southern troposphere meridional circulation to historical maxima of Antarctic sea ice.

The variability of Antarctic sea ice (ASI) has great potential to affect atmospheric circulation, with impacts that can extend from the surface to the middle and high levels of troposphere. The present study has evaluated the response of South Atlantic tropospheric circulation to increased coverage in area and volume of ASI. Monthly data of air temperature, zonal and meridional wind and mean sea level pressure were obtained from two ensemble simulations performed with the GDFL/CM2.